Stereo camera

Abstract

A stereo camera optimally corrects a parallax despite a photographing distance. Lens boards of right and left photographing lenses are mounted with slide guides for obliquely feeding in an inter-optical axis distance approaching direction as the lens boards are fed. When a focusing knob is rotated, the photographing lenses and a finder lens are integrally advanced or retracted in response to the rotating direction of a cam shaft. The slide guides are so disposed that the right and left visual fields are brought into agreement at a close distance at the close distance photographing and the right and left visual fields are brought into agreement at the close distance as compared with the focal distance at the time of remote distance photographing. Accordingly, the unnatural of the remote or close distance feeling generated by the influence of the close distance subject at the human collimation at the time of remote distance photographing, and ideal stereo effect is obtained at all the photographing distances.

I claim: 
     
       1. A stereo camera comprising an automatic inter-optical axis distance correcting mechanism having independent lens boards having sliders mounting two photographing lenses having optical axes, visual fields, and a shortest focal distance for moving the lens boards in parallel in approaching directions as the lens boards are moved by a focusing mechanism so that the optical axes of the two photographing lenses approach to being the visual fields of the two photographing lenses at a focal position into coincidence, and slide guides of the lens boards provided to move on a linear line to a position where principal points of the two photographing lenses are shifted in the approaching direction from right and left picture pitches at an infinite remote focal position to another position where the visual fields of the two photographing lenses are brought into coincidence at the shortest focal distance, thereby automatically correcting the distance between the optical axes by the slide guides coupled to the sliders and the focusing mechanism. 
     
     
       2. A stereo camera comprising: a camera body;   a first lens board slidebly mounted on said camera body;   a first lens placed within said first lens board, said first lens having a first optical axis and a first visual field;   a second lens board slidebly mounted on said camera body;   a second lens placed within said second lens board, said second lens having a second optical axis and a second visual field, the first optical axis and the second optical axis being separated by a distance;   focusing means, coupled to said first lens and said second lens, for moving said first lens along the first optical axis and said second lenses along the second optical axis and focusing on a principal subject,   cam means, coupled to focusing means and said first and second lens boards, for moving said first lens and said second lens each along a linear path that is tangent to a smooth exponential curved line formed by a path that would bring the right and left visual fields into agreement correcting for parallax,   whereby upon focusing on the principal subject the distance between said first optical axis and said second optical axis is changed correcting for parallax resulting in an improved stereo image.   
     
     
       3. A stereo camera as in claim 2 wherein: the smooth exponential curve is formed according to the following equation,   s/=(P.sub.1 /2)×(f+if/L+f+if)     where,     P 1  =a pitch between a first and second exposing surface,   f=a focal distance of said first and second lens,   L=distance from a subject to a principal point of said first and second lenses,   if=distance from a focal point of said first and second lenses to an image forming position.   
     
     
       4. A stereo camera as in claim 2 wherein: the linear paths are tangent at a point where said first and second lenses are at a shortest photographing distance point.   
     
     
       5. A stereo camera comprising: a camera body;   a first lens board slidebly mounted on said camera body;   a first lens placed within said first lens board, said first lens having a first optical axis;   a second lens board slidebly mounted on said camera body;   a second lens placed within said second lens board, said second lens having a second optical axis, the first optical axis and the second optical axis being separated by a distance;   a first arm attached at one end to said first lens board;   a second arm attached at one end to said second lens board;   a first cam placed on said first arm;   a second cam placed on said second arm;   a cam shaft coupled to said first cam and said second cam;   focusing means, coupled to said cam shaft, for focusing on a principal subject,   whereby upon focusing on the principal subject the distance between said first optical axis and said second optical axis is changed correcting for parallax resulting in an improved stereo image.   
     
     
       6. A stereo camera comprising: a camera body;   a right slider guide engaging said camera body;   a right lens board slidebly mounted on said right slider guide, said right slider guide obliquely sliding said right lens board;   a right photographing lens placed within said right lens board, said right photographing lens having a first optical axis;   a left slider guide engaging said camera body;   a left photographing lens board slidebly mounted on said left slider guide, said left slider guide obliquely sliding said left lens board;   a left lens placed within said left lens board, said left lens having a second optical axis, the first optical axis and the second optical axis being separated by a distance;   a central slider guide placed between said right slider guide and said left slider guide;   a finder lens place within said central slider guide;   a right arm attached at one end to said right lens board;   a left arm attached at one end to said left lens board;   a center arm attached at one end to said finder lens;   a first cam placed on said first arm;   a second cam placed on said second arm;   a third cam placed on said center arm;   a cam shaft coupled to said first, second, and third cams;   focusing means, attached to said cam shaft, for adjusting the focus of said finder lens,   whereby upon focusing on the principal subject the distance between said first optical axis and said second optical axis is changed correcting for parallax resulting in an improved stereo image.